leave the program and go on missions. The list is extremely short.
Jackson Emery played in 05-06 then went on a mission
KC played 10-11 before his mission
T. Haws played 09-10 before his mission
CC played 07-08 before going on his mission.
On average you have less than one scholarship freshman leaving on a mission.
Rose has a lot of recruits go on missions directly out of HS, or has them walk on or grey shirt, rather than having scholarship freshman for a year, then have them go on missions.
The only other two players (other than the 4 above) who were on roster before and after a mission are Martineau and Zylstra. I don't believe either of them were on scholarship before their missions.